Neiko 20713A Digital Tachometer, Non Contact Laser Photo | 2.5 - 99,999 RPM Accuracy | Batteries Included Highly accurate non-contact digital tachometer with high speed laser-aim operation and instant readings from 2.5 to 99,999 RPM Readings are displayed on a large, easy-to-read LCD screen; stores last, minimum, and maximum reading; features auto-zero adjustment Includes 24-inches of reflective tape and aim and measure design for non-contact diagnostics and measurements Compact and lightweight, operates for hours on three included AA batteries; perfect for measuring motors, machine parts, lathes, etc. Accurate to +/- 0.05 percent and capable of measuring at a distance from 2-20 inches; RPMs measured over 1 second sampling time